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 * Copyright (c) 2000, 2002, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package javax.swing.plaf.basic;

import sun.datatransfer.DataFlavorUtil;

import java.io.*;
import java.awt.datatransfer.*;
import javax.swing.plaf.UIResource;


A transferable implementation for the default data transfer of some Swing
components.

Author: Timothy Prinzing
/**
 * A transferable implementation for the default data transfer of some Swing
 * components.
 *
 * @author  Timothy Prinzing
 */
class BasicTransferable implements Transferable, UIResource {

    protected String plainData;
    protected String htmlData;

    private static DataFlavor[] htmlFlavors;
    private static DataFlavor[] stringFlavors;
    private static DataFlavor[] plainFlavors;

    static {
        try {
            htmlFlavors = new DataFlavor[3];
            htmlFlavors[0] = new DataFlavor("text/html;class=java.lang.String");
            htmlFlavors[1] = new DataFlavor("text/html;class=java.io.Reader");
            htmlFlavors[2] = new DataFlavor("text/html;charset=unicode;class=java.io.InputStream");

            plainFlavors = new DataFlavor[3];
            plainFlavors[0] = new DataFlavor("text/plain;class=java.lang.String");
            plainFlavors[1] = new DataFlavor("text/plain;class=java.io.Reader");
            plainFlavors[2] = new DataFlavor("text/plain;charset=unicode;class=java.io.InputStream");

            stringFlavors = new DataFlavor[2];
            stringFlavors[0] = new DataFlavor(DataFlavor.javaJVMLocalObjectMimeType+";class=java.lang.String");
            stringFlavors[1] = DataFlavor.stringFlavor;

        } catch (ClassNotFoundException cle) {
            System.err.println("error initializing javax.swing.plaf.basic.BasicTranserable");
        }
    }

    public BasicTransferable(String plainData, String htmlData) {
        this.plainData = plainData;
        this.htmlData = htmlData;
    }


    
Returns an array of DataFlavor objects indicating the flavors the data
can be provided in.  The array should be ordered according to preference
for providing the data (from most richly descriptive to least descriptive).

Returns:an array of data flavors in which this data can be transferred
/**
     * Returns an array of DataFlavor objects indicating the flavors the data
     * can be provided in.  The array should be ordered according to preference
     * for providing the data (from most richly descriptive to least descriptive).
     * @return an array of data flavors in which this data can be transferred
     */
    public DataFlavor[] getTransferDataFlavors() {
        DataFlavor[] richerFlavors = getRicherFlavors();
        int nRicher = (richerFlavors != null) ? richerFlavors.length : 0;
        int nHTML = (isHTMLSupported()) ? htmlFlavors.length : 0;
        int nPlain = (isPlainSupported()) ? plainFlavors.length: 0;
        int nString = (isPlainSupported()) ? stringFlavors.length : 0;
        int nFlavors = nRicher + nHTML + nPlain + nString;
        DataFlavor[] flavors = new DataFlavor[nFlavors];

        // fill in the array
        int nDone = 0;
        if (nRicher > 0) {
            System.arraycopy(richerFlavors, 0, flavors, nDone, nRicher);
            nDone += nRicher;
        }
        if (nHTML > 0) {
            System.arraycopy(htmlFlavors, 0, flavors, nDone, nHTML);
            nDone += nHTML;
        }
        if (nPlain > 0) {
            System.arraycopy(plainFlavors, 0, flavors, nDone, nPlain);
            nDone += nPlain;
        }
        if (nString > 0) {
            System.arraycopy(stringFlavors, 0, flavors, nDone, nString);
            nDone += nString;
        }
        return flavors;
    }

    
Returns whether or not the specified data flavor is supported for
this object.

Params:
  • flavor – the requested flavor for the data
Returns:boolean indicating whether or not the data flavor is supported
/**
     * Returns whether or not the specified data flavor is supported for
     * this object.
     * @param flavor the requested flavor for the data
     * @return boolean indicating whether or not the data flavor is supported
     */
    public boolean isDataFlavorSupported(DataFlavor flavor) {
        DataFlavor[] flavors = getTransferDataFlavors();
        for (int i = 0; i < flavors.length; i++) {
            if (flavors[i].equals(flavor)) {
                return true;
            }
        }
        return false;
    }

    
Returns an object which represents the data to be transferred.  The class
of the object returned is defined by the representation class of the flavor.

Params:
  • flavor – the requested flavor for the data
Throws:
See Also:
/**
     * Returns an object which represents the data to be transferred.  The class
     * of the object returned is defined by the representation class of the flavor.
     *
     * @param flavor the requested flavor for the data
     * @see DataFlavor#getRepresentationClass
     * @exception IOException                if the data is no longer available
     *              in the requested flavor.
     * @exception UnsupportedFlavorException if the requested data flavor is
     *              not supported.
     */
    public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException {
        DataFlavor[] richerFlavors = getRicherFlavors();
        if (isRicherFlavor(flavor)) {
            return getRicherData(flavor);
        } else if (isHTMLFlavor(flavor)) {
            String data = getHTMLData();
            data = (data == null) ? "" : data;
            if (String.class.equals(flavor.getRepresentationClass())) {
                return data;
            } else if (Reader.class.equals(flavor.getRepresentationClass())) {
                return new StringReader(data);
            } else if (InputStream.class.equals(flavor.getRepresentationClass())) {
                return createInputStream(flavor, data);
            }
            // fall through to unsupported
        } else if (isPlainFlavor(flavor)) {
            String data = getPlainData();
            data = (data == null) ? "" : data;
            if (String.class.equals(flavor.getRepresentationClass())) {
                return data;
            } else if (Reader.class.equals(flavor.getRepresentationClass())) {
                return new StringReader(data);
            } else if (InputStream.class.equals(flavor.getRepresentationClass())) {
                return createInputStream(flavor, data);
            }
            // fall through to unsupported

        } else if (isStringFlavor(flavor)) {
            String data = getPlainData();
            data = (data == null) ? "" : data;
            return data;
        }
        throw new UnsupportedFlavorException(flavor);
    }

    private InputStream createInputStream(DataFlavor flavor, String data)
            throws IOException, UnsupportedFlavorException {
        String cs = DataFlavorUtil.getTextCharset(flavor);
        if (cs == null) {
            throw new UnsupportedFlavorException(flavor);
        }
        return new ByteArrayInputStream(data.getBytes(cs));
    }

    // --- richer subclass flavors ----------------------------------------------

    protected boolean isRicherFlavor(DataFlavor flavor) {
        DataFlavor[] richerFlavors = getRicherFlavors();
        int nFlavors = (richerFlavors != null) ? richerFlavors.length : 0;
        for (int i = 0; i < nFlavors; i++) {
            if (richerFlavors[i].equals(flavor)) {
                return true;
            }
        }
        return false;
    }

    
Some subclasses will have flavors that are more descriptive than HTML
or plain text.  If this method returns a non-null value, it will be
placed at the start of the array of supported flavors.

/**
     * Some subclasses will have flavors that are more descriptive than HTML
     * or plain text.  If this method returns a non-null value, it will be
     * placed at the start of the array of supported flavors.
     */
    protected DataFlavor[] getRicherFlavors() {
        return null;
    }

    protected Object getRicherData(DataFlavor flavor) throws UnsupportedFlavorException {
        return null;
    }

    // --- html flavors ----------------------------------------------------------

    
Returns whether or not the specified data flavor is an HTML flavor that
is supported.

Params:
  • flavor – the requested flavor for the data
Returns:boolean indicating whether or not the data flavor is supported
/**
     * Returns whether or not the specified data flavor is an HTML flavor that
     * is supported.
     * @param flavor the requested flavor for the data
     * @return boolean indicating whether or not the data flavor is supported
     */
    protected boolean isHTMLFlavor(DataFlavor flavor) {
        DataFlavor[] flavors = htmlFlavors;
        for (int i = 0; i < flavors.length; i++) {
            if (flavors[i].equals(flavor)) {
                return true;
            }
        }
        return false;
    }

    
Should the HTML flavors be offered?  If so, the method
getHTMLData should be implemented to provide something reasonable.

/**
     * Should the HTML flavors be offered?  If so, the method
     * getHTMLData should be implemented to provide something reasonable.
     */
    protected boolean isHTMLSupported() {
        return htmlData != null;
    }

    
Fetch the data in a text/html format

/**
     * Fetch the data in a text/html format
     */
    protected String getHTMLData() {
        return htmlData;
    }

    // --- plain text flavors ----------------------------------------------------

    
Returns whether or not the specified data flavor is an plain flavor that
is supported.

Params:
  • flavor – the requested flavor for the data
Returns:boolean indicating whether or not the data flavor is supported
/**
     * Returns whether or not the specified data flavor is an plain flavor that
     * is supported.
     * @param flavor the requested flavor for the data
     * @return boolean indicating whether or not the data flavor is supported
     */
    protected boolean isPlainFlavor(DataFlavor flavor) {
        DataFlavor[] flavors = plainFlavors;
        for (int i = 0; i < flavors.length; i++) {
            if (flavors[i].equals(flavor)) {
                return true;
            }
        }
        return false;
    }

    
Should the plain text flavors be offered?  If so, the method
getPlainData should be implemented to provide something reasonable.

/**
     * Should the plain text flavors be offered?  If so, the method
     * getPlainData should be implemented to provide something reasonable.
     */
    protected boolean isPlainSupported() {
        return plainData != null;
    }

    
Fetch the data in a text/plain format.

/**
     * Fetch the data in a text/plain format.
     */
    protected String getPlainData() {
        return plainData;
    }

    // --- string flavorss --------------------------------------------------------

    
Returns whether or not the specified data flavor is a String flavor that
is supported.

Params:
  • flavor – the requested flavor for the data
Returns:boolean indicating whether or not the data flavor is supported
/**
     * Returns whether or not the specified data flavor is a String flavor that
     * is supported.
     * @param flavor the requested flavor for the data
     * @return boolean indicating whether or not the data flavor is supported
     */
    protected boolean isStringFlavor(DataFlavor flavor) {
        DataFlavor[] flavors = stringFlavors;
        for (int i = 0; i < flavors.length; i++) {
            if (flavors[i].equals(flavor)) {
                return true;
            }
        }
        return false;
    }


}